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Tobacco growers tend to go with what has worked in the past—and just as surely, they look for new solutions when things do not work as they planned.

That fact is not lost on those who provide tobacco seed for growers each year. These seed specialists grow and develop multiple varieties of seed for a grower. While they magnify good characteristics that a grower has come to rely on, they are constantly working to develop varieties with particular characteristics that may give a grower an edge with a recurrent problem or lift his bottom line with additional quality and quantity at season’s end.

As growers prepare their 2009 crop, seed specialists have already prepared their wares for growers, whether they are looking to continue what works or are considering making a switch.

Disease or yield?
The first order of business, as always, is which characteristic in a seed variety is more important—disease resistance or improved yield?

“This is the proverbial ‘double-edged sword’ question,” said Sam Baker of Cross Creek Seed. “Farmers are looking for tobacco seed companies to develop varieties with both disease resistance and high yields. If one was forced to choose one or the other, they would choose high-yielding varieties and apply chemicals such as Ridomil for black shank and fumigants to help control nematodes and Granville wilt.”

Like Baker, Jimmy Bennett of Gold Leaf Seed knows growers demand both, not one or the other. “Growers are interested in varieties that have both disease resistance and yield,” he said.

Todd Taylor of F.W. Rickard Seed concurs. “They want the best of both worlds,” he said. “Generally, the breeding of disease resistance has an adverse affect on yield without the presence of the targeted disease.”

The 2008 North Carolina Tobacco Guide, produced by North Carolina State University, cautions growers to look at disease resistance first when considering a seed choice. Resistance to the flue-cured crop’s two most persistent enemies in the state—black shank and Granville wilt—are paramount in selection, considering that a crop’s improved yield or added poundage is meaningless if the crop fails from disease.

While seed selection is important, a grower can improve his disease prevention odds by reducing his disease exposure. Fields with disease pressure need to be laid fallow if at all possible to reduce the likelihood of a return. The North Carolina guide reminds growers to “determine the level of disease resistance that you need based on field history, length of rotation, and crops grown in rotation with tobacco.”

“If agronomic practices or pesticide controls are effective in controlling disease pressure present in a field, then higher yields will be the driver for variety choices made by a farmer,” says Taylor.

Results of variety trials for individual state are easily obtained and are printed in the state’s production guides each year.

Is black shank beaten?
Black shank resistance has come a long way, but there is no true answer to both race 1 and race 0 as of yet.

“At the present time there are no current varieties that have the resistance to race 0 and race 1,” said Bennett. “Some varieties have resistance to race 0 and others have shown tolerance to race 1, but no total resistance. We feel that research will provide better resistance in a few years.”

Baker noted that by using pH gene varieties, race 0 resistance has been achieved.

“The problem comes with race 1 black shank,” he said. “For three years running, there are only two legitimate variety choices for Race 1 control—Speight 227 and Speight 225. Both varieties stand up 25-35 percent better than the other considered option, K 346, while offering better Granville wilt resistance and a slight yield boost versus K 346 as well.”

Baker said that improved resistance to race 1 is on the way. “(Resistance to) race 0 black shank and resistance to mosaic is becoming more common with new varieties, along with added nematode resistances,” Baker said. “(Building resistance to) TSWV is a little more complicated.”

Taylor says that some burley varieties have high resistance to both races of black shank—and even better resistance may be ahead. “KT 204LC and KT 206LC have the highest resistance of any burley variety to both black shank race 0 and 1,” he says. “It is anticipated that … a new variety with even higher black shank race 1 resistance will be released in the near future.”

Dark tobacco varieties have been developed with medium resistance to both races of black shank, but “at this point breeding resistance to black shank race 1 may reduce leaf quality,” says Taylor. “In flue-cured varieties black shank race 0 can be handled pretty well with resistant varieties or the use of fungicides, with few registered varieties doing well against race 1.”

Rickard plans to introduce PVH 1452 in 2010, which has good resistance to black shank race 0 and moderate resistance to race 1.

But the ultimate answer may come with acceptance of GM tobacco varieties.

“The industry already has resistance to TSWV in some GMO varieties,” said Bennett. “But until the cigarette companies feel that the public accepts GMO developed varieties, they cannot be sold.”

Taylor feels the same.

“GM tobacco is not currently acceptable in today’s tobacco environment,” he says. “There are several areas where GM varieties can help, such as disease resistance, herbicide resistance and insect resistance.”

Taylor adds that using GM tobacco as a harm-reduction tool is likely the best way to gain any acceptance, and that is many years away.

“While some very small steps have been made through breeding, in all likelihood it will take GMO-transgenic tobacco to fully combat this issue,” added Baker.

Seeding systems
More growers in large operations are converting to automated seeding lines, using down seeders and rolling dibbles.

“That is a more consistent process than the old way,” said Lisa Cobb of Carolina Greenhouses. “Using an automated method is a good option for a grower who has to seed in one to two days.”

Cobb’s company rents the equipment necessary to create an automated line, but it can be purchased. It will have to be fumigated and cleaned, just as the trays do.

Baker said a big key to getting the most from the seed dollar was in selecting a seed or pellet that has a melt-down component that will germinate within three days from beginning to end. That results in uniformity and provides the means to save later in the transplant production process.

Taylor reinforces the notion that good practices in the greenhouse are the best protection of investment.

“Manage greenhouses to produce uniform healthy transplants,” he says. “Manage ventilation to reduce the time seed and plants are exposed to excessive heat, control humidity to aid in disease control, clip plants to promote uniformity while helping to control diseases, do not overfertilize and only use labeled pesticides in the greenhouse.”

Doing it wisely
Getting the most from your seed dollar, according to Baker, is a multi-step process.

“Select a variety that produces high yields with high quality,” he said. “Manage the greenhouse properly—temperature and air movement, look for disease pressure early and often. Check pH levels, both in both water and in the soil media.”

Baker said the pH situation is an ever-growing one. “If the seed germinates well, then after 10-15 days the seed disappears, then you most likely have a problem with the pH in the media,” he said.

Bennett was mindful of how cost-efficient tobacco seeds are in comparison to other crops.

“Presently, tobacco growers have their best investment dollars in purchase of tobacco seed for a crop that grosses between $3,500 and $4,000 per acre, with seed cost that averages about $13 an acre,” he said. “Compare that with $20 cost per acre for soybeans, $38 per acre for corn and $60 per acre for cotton.”